In order to explore the influence of water and fertilizer coupling on the water consumption rule of drip irrigated grape in extreme arid area

the distribution of water use in each growth stage and the dynamic changes in the whole growth stage were investigated under different water and fertilizer combinations. Then the crop coefficient of drip irrigated grape was determined in the area using the water balance method and the Penman-Montes formula. The age-old seedless white grape in the test area was taken as a research object

and two factors of irrigation and fertilization were set

including four irrigation treatments:600

675

750

825 mm (labeled W1

W2

W3

W4

respectively); three fertilization treatments:450

750

1 050 kg/hm2 (labeled F1

F2

F3

respectively). The results showed that the average soil water contents increased with the increases of irrigation quota. The water contents of W3 and W4 were 13.35% and 14.04%

respectively

both of which were higher than 12.80% (80% of field water holding capacity)

indicating the sufficient water supply. The effects of water and fertilizer coupling on yields and quality indicators reached the very significant level (P<0.01). The yield and soluble solids reached the highest value in W3F2

but the titratable acid and vitamin C performaned best in W4F2 and W4F3

respectively. There was no significant difference in W3F2 (P>0.05). Under different treatments

irrigation had significant effects on the total water consumption and water consumption and water consumption intensities during each growth period (P<0.05)

but the corresponding effects of fertilization did not reach significant level (P>0.05). The water-fertilizer coupling had a significant effect on the water consumption intensity during each growth period (P<0.05). The total water consumptions were maintained between 665.96 and 902.90 mm under the different treatments. The water consumption and water consumption intensities of each treatment increased first and then decreased during the growth periods. There was a significant quadratic curve relationship between water consumption intensities and time. The mean water consumption modulus of each treatment in the berry growth period and berry ripening period was 27.01%~27.36%

which was the peak of grape water demand. The water consumption law under W3F2 could be regarded as the regional water requirement of grape. The grape crop coefficient generally increased first and then decreased during the growth periods showing a significant quadratic curve relationship with time. This study could provide a scientific basis for the promotion of water and fertilizer management and drip irrigation technology in the non-nuclear white grape farmland in similar areas of the Tuha Basin. It also could be of great significance for the efficient use of regional water resources and the realization of sustainable socio-economic development regionally.